The Rhinemaidens arrived in a Mercedes convertible, Brünnhilde lived in an Airstream trailer and the New York Stock Exchange all figured in a demented production of “The Ring” at Germany’s Bayreuth Festival. Photo: Courtesy of Bayreuth Festival

The New York Stock Exchange factors big in Germany's famous Wagner festival.

The apocalypse was the climax of “Der Ring des Nibelungen,” as the demigoddess Brünnhilde returned a cursed golden ring to the Rhine River — which in this case flowed directly in front of the New York Stock Exchange.

But what’s the NYSE doing in Wagner’s “Ring,” especially one performed at Germany’s famous Bayreuth Festival?

As director Frank Castorf sees it, the all-powerful element everyone’s fighting over these days isn’t gold but oil. So he moved the “Ring” from legendary times in Northern Europe to a perplexing variety of eras and locales worthy of “Cloud Atlas.”

Revolving sets five stories high depicted not only Wall Street but a motel on Route 66, a subway station in 1980s East Germany and an oil field in pre-revolutionary Russia. Rhinemaidens rode onstage in a Mercedes convertible and Brünnhilde and Siegfried lived in an Airstream trailer.

Another part of “The Ring” was set on America’s famous Route 66.Photo: Courtesy of Bayreuth Festival

All told, this surrealistic “Ring”— which will probably never play New York — was a far cry from Robert Lepage’s production for the Met which, despite its high-tech stage machinery, essentially relates Wagner’s plot as written.

Then again, with 15 hours of music spread over four nights, the “Ring” has always been a challenge. For the premiere back in 1876, Wagner went so far as to build his own opera house, the Festspielhaus, in the Bavarian village of Bayreuth.

Since the ’50s, that once-quiet town has been home to a Wagnerian festival of cutting-edge stagings. This summer’s “Lohengrin” portrayed the title character, a knight in shining armor, as a psychological test subject confronted by an army of human-size rats.

But Castorf, a fixture of Germany’s avant-garde theater for more than 40 years, may have pushed Bayreuth’s open-minded audience too far with his radical restaging of “Ring” — loud boos rang out in the theater after just about every act.

Winning equally loud bravos, though, were baritone Wolfgang Koch as Wotan, king of the gods, and soprano Anja Kampe as his mortal daughter Sieglinde. Another audience favorite was tenor Burkhard Ulrich as Mime, a dwarf who schemes to steal the ring.

Of course, in this version, he’s no dwarf at all, but rather a schizophrenic Unabomber type who’s holed up in a cliff carved into a parody of Mount Rushmore — only the faces here included Stalin and Mao.

What did it all mean? I can’t tell you for sure: Castorf’s take on this saga was bewildering, terrifying — and yet strangely compelling: Just the way Wagner would have wanted it.